* Skoda wants annual sales of 500,000 by 2018
* Could mean a third of its sales go to China by then
PRAGUE, April 25 (Reuters) - Czech carmaker Skoda Auto, a unit of Volkswagen, aims to double its sales in China to 500,000 vehicles by 2018, when one-third of its annual output could go to the world's biggest car market.
Skoda, a bellwether for the Czech economy, has plans to raise its annual global sales to at least 1.5 million cars by 2018, up from a record 939,200 vehicles in 2012.
Despite troubles in Europe, where car sales are falling overall, the company said last month it was on course to meet its goal, and like other global carmakers, it is counting on growth in key emerging markets such as China or Russia.
Skoda said on Thursday it was doubling its model range in China to six this year.
"Our aim is to increase sales in China to around half a million vehicles by 2018," Skoda Chief Executive Winfried Vahland said in a statement.
Light vehicle sales in China reached more than 19 million last year, and some analysts estimate that could grow to more than 30 million in the next decade.
Skoda started selling in China nearly six years ago and has sold 913,800 cars in that time, including 235,700 vehicles in 2012. The country has been its top market since 2010.
Volkswagen said this month that it planned to increase its Chinese workforce by a third to more than 100,000 people by 2018 as the company continues to expand its local production capacity, which includes some Skoda models.
Skoda is the top exporter in the Czech Republic, where exports amount to 80 percent of annual economic output.
The central European economy has been stuck in recession since the middle of 2011, with demand for Czech exports from the euro zone waning and domestic demand hit by the centre-right government's spending cuts and tax hikes.
(Reporting by Jason Hovet; Editing by Elaine Hardcastle)